A Cyborg Heart

Andrew Sullivan —  Jun 1 2013 @ 8:52am

You may be able to get one soon:

[W]ith demand for heart transplants far exceeding donations, patients can wait for years for a carmat-systeme_01donor heart, while others may be ineligible altogether because of other health issues. An artificial heart can provide a life-saving bridge while a patient waits for a transplant. Surgeons have implanted [the only currently approved artificial heart] in over 1,000 patients. Air is pumped from the external control system (which has recently evolved from a large, 418-pound [air-]driver to a wearable 13.5-pound driver) through tubes that connect through the skin into the device. Puffs of air expand two small balloons inside each chamber of the artificial heart, which pushes blood out of the prosthesis.

[However, in Carmat’s new design,] two chambers are each divided by a membrane that holds hydraulic fluid on one side.

A motorized pump moves hydraulic fluid in and out of the chambers, and that fluid causes the membrane to move; blood flows through the other side of each membrane. The blood-facing side of the membrane is made of tissue obtained from a sac that surrounds a cow’s heart, to make the device more biocompatible. “The idea was to develop an artificial heart in which the moving parts that are in contact with blood are made of tissue that is [better suited] for the biological environment,” says Piet Jansen, chief medical officer of Carmat.

That could make patients less reliant on anti-coagulation medications. The Carmat device also uses valves made from cow heart tissue and has sensors to detect increased pressure within the device. That information is sent to an internal control system that can adjust the flow rate in response to increased demand, such as when a patient is exercising.

(Image: Carmat Wearable Heart System)